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an art illustration done by AI
'We Should Be Looking for Small, Hot Dyson Spheres'
https://www.universetoday.com/163201/we … n-spheres/
In 1960, legendary physicist Freeman Dyson published his seminal paper “Search for Artificial Stellar Sources of Infrared Radiation,” wherein he proposed that there could be extraterrestrial civilizations so advanced that they could build megastructures large enough to enclose their parent star. He also indicated that these “Dyson Spheres,” as they came to be known, could be detected based on the “waste heat” they emitted at mid-infrared wavelengths. To this day, infrared signatures are considered a viable technosignature in the Search for Extraterrestrial Intelligence (SETI).
So far, efforts to detect Dyson Spheres (and variation thereof) by their “waste heat” signatures have come up empty, leading some scientists to recommend tweaking the search parameters. In a new paper, astronomy and astrophysics Professor Jason T. Wright of the Center for Exoplanets and Habitable Worlds and the Penn State Extraterrestrial Intelligence Center (PSTI) recommends that SETI researchers refine the search by looking for indications of activity. In other words, he recommends looking for Dyson Spheres based on what they could be used for rather than just heat signatures.
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Hyades Star Cluster Revelations: Earth’s Nearest Black Holes Uncovered
https://scitechdaily.com/hyades-star-cl … uncovered/
Researchers suggest the presence of several black holes in the Hyades cluster, potentially the closest to Earth, using simulations and data from the Gaia space telescope.
Similar to a previous UniverseToday Article
Advanced life should have already peaked billions of years ago, says paper
https://phys.org/news/2023-05-advanced- … years.html
Garofalo explains how black hole feedback can either drive or suppress star formation. Whether it does or not depends on the environment and whether the SMBH is in a gas-sparse or a gas-rich environment.
Where Are All the Aliens — the Fermi Paradox
https://medium.com/@SJsenthil/where-are … 4f74467938
Gaia is Now Finding Planets. Could it Find Another Earth?
The ESA launched Gaia in 2013 with one overarching goal: to map more than one billion stars in the Milky Way. Its vast collection of data is frequently used in published research. Gaia is an ambitious mission, though it seldom makes headlines on its own.
But that could change.
Gaia relies on astrometry for much of its work, and astrometry is the measurement of the position, distance, and motions of stars. It’s so sensitive that it can sometimes detect the slight wobble a planet imparts to its much more massive star. Gaia detected its first two transiting exoplanets in 2021, and it’s expected to find thousands of Jupiter-size exoplanets beyond our Solar System.
But new research takes it even further. It shows that Gaia should be able to detect Earth-like planets up to 30 light-years away.
The new paper is “The Possibility of Detecting our Solar System Through Astrometry,” and is available on the pre-press site arxiv.org. It has a single author: Dong-Hong Wu from the Department of Physics, Anhui Normal University, Wuhu, Anhui, China.
Astronomers find most exoplanets with the transit method. A spacecraft like TESS monitors a section of the sky and looks at many stars at once. When a planet passes between us and one of the stars, it’s called a transit. It creates a dip in starlight that TESS’s sensitive instruments can detect. When TESS detects multiple, predictable dips, it signifies a planet.
But that’s not the only way to detect them. Astrometry can do it too, and that’s Gaia’s way.
Astrometry has an advantage over other methods. Gaia can more accurately determine an exoplanet’s orbital parameters. This doesn’t mean the other methods aren’t valuable. They obviously are. But as the paper’s author explains, “Neither the transit nor radial velocity method provides complete physical parameters of one planet, and both methods prefer to detect planets close to the central star. On the contrary, the astrometry method can provide a three-dimensional characterization of the orbit of one planet and has the advantage of detecting planets far away from the host star.” Astrometry’s advantages are clear.
If other technological planetary civs exist—and that’s a big if—then it’s not outrageous to think they have technology similar to Gaia’s. While Gaia is impressive, there are improvements on the horizon that will make astrometry even more precise. The author asks a question in his paper: If ETIs (ExtraTerrestrial Intelligences) are using advanced astrometry equal to or even surpassing Gaia’s, “…which of them could discover the planets in the solar system, even the Earth?”
Astrometrical precision is calculated in microarcseconds, and precision decreases with distance. The ESA says that Gaia can measure a star’s position within 24 microarcseconds for objects 4000 times fainter than the naked eye. That’s like measuring the thickness of a human hair from 1000 km away. But that’s not precise enough for Wu’s scenario. His work is based on even more advanced astrometry, the type we’ll likely have in the near future. “If the astrometry precision is equal to or better than ten microarcseconds, all 8,707 stars located within 30 pcs of our solar system possess the potential to detect the four giant planets within 100 years.”
This is the heart of Wu’s paper. The 30-parsec (approx. 100 light-years) region contains almost 9,000 stars, and if an ETI from one of those stars has powerful enough astrometry, then it could detect Jupiter, Saturn, Uranus, and Neptune. The only drawback is they’d have to observe our Solar System for nearly a century to make sure the signal was clear.
https://www.universetoday.com/163347/ga … her-earth/
also news about a new telescope
'GaiaNIR'
A future astrometry mission
Last edited by Mars_B4_Moon (2023-09-25 20:04:46)
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2 Missions to Jupiter's strange world Europa, more missions to the Moons of Saturn and Mars.
James Webb telescope sees potential signs of something...we are not sure...but no fTL Warp drive to check it out up close and personal
Why finding alien life in Universe is now 'only a matter of time'
https://www.bbc.com/news/science-environment-66950930
Last edited by Mars_B4_Moon (2023-10-01 06:01:26)
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For Mars_B4_Moon re #53
Thank you for finding and posting the link to the BBC story on the search for alien life ...
By Pallab Ghosh
Science correspondent
Many astronomers are no longer asking whether there is life elsewhere in the Universe.
The question on their minds is instead: when will we find it?
The report by Pallab Ghosh was unusually rich in text and images.
(th)
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The Zoo Hypothesis: A "Psychologically Unpleasant" Idea Why Aliens Haven't Made Contact
https://www.iflscience.com/the-zoo-hypo … tact-70853
Could this explain why aliens haven't been in touch?
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Astrobiology and exobiology topic
The scientists looking for alien vegetation
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Wow. JWST Just Found Methane in an Exoplanet Atmosphere
https://www.universetoday.com/164405/wo … tmosphere/
It’s not a slam dunk because it has both biotic and abiotic sources. But finding it in an exoplanet’s atmosphere means that planet deserves a closer look.
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and yet we can not truly have communication with our own animals and a debate on consciousness
Elephants give each other names — the 1st non-human animals to do so, study claims
https://www.livescience.com/animals/ele … udy-claims
Last edited by Mars_B4_Moon (2023-11-25 12:28:27)
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The first non-human animals to do so (give each other names) that we know about, would be a more accurate assessment.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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David H. Grinspoon an American astrobiologist.
'Hotel Mars Dr. David Grinspoon'
https://www.thespaceshow.com/show/20-de … -grinspoon
The first non-human animals to do so (give each other names) that we know about, would be a more accurate assessment.
GW
very true indeed with news on Whales, researchers have now suggested that whales have syntax, dialects, names and culture in their vocalization song.
Scientists had a groundbreaking conversation with a humpback whale in her own language and it could help humans chat with aliens one day
https://uk.news.yahoo.com/whales-teachi … 14681.html
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NASA identifies 17 planets with possible subsurface oceans, and they could be fit for life
https://www.livescience.com/space/exopl … t-for-life
Project Longshot an interstellar spacecraft design which possibly could have been an uncrewed starship 400 tonnes, intended to fly to and enter orbit around Alpha Centauri B powered by nuclear pulse propulsion, new unknown technology and similar to other radical ideas like 'Orion' and Project Daedalus.
The reactor would also be used to power a laser for communications back to Earth, with a maximum power of 250 kW.
https://www.realclearscience.com/lists/ … _projects/
Last edited by Mars_B4_Moon (2023-12-25 11:18:33)
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After all of This Time Searching for Aliens, is it The Zoo Hypothesis or Nothing?
https://www.universetoday.com/165005/af … ypothesis/
Interest in Fermi’s question has been piqued in recent years thanks to the sheer number of “potentially habitable” exoplanets discovered in distant star systems. Despite that, all attempts to find signs of technological activity (“technosignatures”) have come up empty. In a recent study, a team of astrobiologists considered the possible resolutions and concluded that only two possibilities exist. Either extraterrestrial civilizations (ETCs) are incredibly rare (or non-existent), or they are deliberately avoiding contact with us (aka. the “Zoo Hypothesis“).
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World-Limits for man an idea before the 'Space Race'
For humans there is a theory argues that human growth beyond Earth will be limited, for humans to survive the space missions must duplicate ecological conditions found back home, the Earthling expansion limited by the absence of life-sustaining regenerative systems.
Aurora Effect and Exo-civilization Settlement, biology of Earth might be incompatible with a would-be settling species, a novel Aurora by Kim Stanley Robinson leading to the Aurora Hypothesis? which even though a world was formally 'habitable' it was not what we would call settle-able. Life could have lots of extreme swings, germs or spores, hot springs and pools cold like the South Pole and just because planets are habitable doesn’t mean that intelligent life can easily colonize there. World in theory could be in a goldilocks zone but difficult, Low Gravity like Ceres, dry lack of water and radiation like Mars, or just hellish runaway greenhouse effect like Venus, there might be no tides and a lack of Moon making oceans stagnant, there could be problems of volcanism or constant 'quakes' shaking your colony, the good lush worlds are hard to find – what they call the Aurora Effect.
The Fermi Paradox: Pancosmorio Theory
https://www.bitchute.com/video/hrOt63J5jMA/
'Isaac Arthur'
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They are now finally researching the cognitive abilities of farm animals now. They are finding indications of the same sorts of emotional and group friendship lives that we and the whales lead. The complexity varies with the complexity of the animal. But it is even there in chickens.
Which makes a lie out of the longstanding assumption that brain physical size is an indicator of intelligence, doesn't it?
Gets back to the old saw about why they spell "assume" the way they do: because it makes an "ass" out of "u" and "me".
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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New Stellar Danger to Exoplanets Identified by Chandra X-ray Observatory
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An AI Simulated Interactions Between Different Kinds of Advanced Civilizations
https://www.universetoday.com/165933/an … lizations/
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AI Could Explain Why We're Not Meeting Any Aliens, Wild Study Proposes
https://www.sciencealert.com/ai-could-e … y-proposes
The Fermi Paradox is the discrepancy between the apparent high likelihood of advanced civilizations existing and the total lack of evidence that they do exist. Many solutions have been proposed for why the discrepancy exists. One of the ideas is the 'Great Filter.' The Great Filter is a hypothesized event or situation that prevents intelligent life from becoming interplanetary and interstellar and even leads to its demise.
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One assumption that is being made today is that any extraterrestrial intelligent life has already surpassed us in abilities, and has the technological basis for communication. It could be that we have surpassed several other civilizations in less developed states than our own?
I look back at my own scientific career of over 50 years and marvel at the discoveries and progress we've made in that time. 500 years ago, heretics were being burned at the stake for asking the questions we routinely discuss on the forum. Only since the 1900s have we even had a clear understanding of the composition of matter and the structure of atoms! I post here as Oldfart1939, but in my lifetime I have had my personal understanding of the Universe and the composition of matter increase by orders of magnitude.
I'm currently working to prepare a 45 minute talk for the Yellowstone Valley Astronomy Association, in Billings, Montana. This talk will be titled "Cosmochemistry-the Chemistry of Where we Came From."
I'm basing this talk on a seminar I heard as a graduate student in 1970 given by Professor Harold C Urey (Nobel Laureate), as he was the founder of this field of endeavor. His Nobel was given in 1934 for the discovery of Deuterium, and his subsequent work on atomic isotopes gave us the Bomb in 1945. I was fortunate to be introduced to him prior to his lecture on the Urey-Miller experiment, which demonstrated that the molecules of life can be produced abiotically by natural phenomena, such as lightning.
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